Fecal excretion of bile acids is positively related to the incidence of colon cancer. The amount of bile acid entering the colon is controlled by the degree of sulfate ester formation. The enzymes responsible for the formation of bile acid sulfates, bile acid sulfotransferases have different activities on several male and female animals, and can be influenced by externally administered sex hormones. This proposal is directed at the isolation of the individual enzymes, and determination of sex-related differences in their chemical and physical properties, in addition to their enzymatic properties. Purification will involve ion exchange chromatography, gel filtration, isoelectric focusing, affinity chromatography and gel electrophoresis. Amino acid and carbohydrate analysis will be determined on individual enzymes prior to molecular weight determination bb sedimentation equilibrium analysis. Procedures will be further developed for the determination and verification of individual sulfate isomers of polyhydroxy bile acids. This will involve application of capillary gas liquid chromatography mass spectrometry and nuclear magnetic resonance spectrometry. The techniques developed here should find application to the analysis of other sulfate containing compounds in nature, as well as to the study of bile acid metabolism in many pathophysiological situations involving the gastrointestinal tract.